Control of signal-lamps.



L. A. HAWKINS.

CONTROL OF SIGNAL LAMPS.

I ARPLIOATION FILED NOV. 20, 1911. 1,090,301 Patented Mar. 17, 1914.

2 SHEETS-SHEET L Witnesses Inventor His fittorneg.

I Lawrence 2%. Hawkins,

L. A. HAWKINS.

001mm, OF SIGNAL LAMPS. APPLICATION FILED NOV. 20, 1911. I 1 090,301 Patented Mar. 17, 1914.

2 SHEETS-flHEET 2.

M v R 0? Witnesses: Y Inventor: Z6 Laurence. JI. Hawkins, a, i, I. Hrs ittorneg UNITED STATES PATENT OFFICE.

LAURENGE A. HAWKINS, OF SGHENECTADY, NEW YORK, ASSIGNOR, BY MESNE ASSIGNMENTS, TO THE UNION SWITCH AND SIGNAL COMPANY, A CORPO- RATION OF PENNSYLVANIA.

CONTROL OF SIGNAL-LAMPS.

Specification of Letters Patent.

Patented Mar. 17,1914.

To all whom it may concern:

Be it known that I, LAURENCE A. HAW- KINS, citizen of the United States, residing at Schenectady, in the county of Schenectady and State of New York, have invented cert'ain new and useful Improvements in the Control of Signal-Lamps, of which the following is a specification.

My invention provides a means for the control of electric lamps over an alternating current transmission line, without the use of line wires other than those comprised in the transmission line.

My invention is particularly adapted to the control of the electric lamps used in railway systems from a central point, such as from a station from which power is supplied to the signaling system. Thus the lamps over a large territory may be controlled from a central point, current being turned on to the lamps in turned off in the morning, thereby prolonging the life of the lamps and avoiding the unnecessary use of current for illuminating the lamps during daylight.

I will describe my invention as applied to two forms of transmission lines used for railway signaling purposes, and will then point out the novel features thereof in the claim.

In the accompanying drawings, Figure 1 is a diagrammatic view showing a railway signaling system supplied from a single phase transmission line, and having a system for the control of the signal lamps embodying my invention applied thereto. Fig. 2 is a view similar to Fig. 1 but showing a system embodying my invention applied to a railway signalingsystem supplied from a polyphase transmission line.

Similar reference characters refer to similar parts in each of the views.

Referring particularly to Fig. 1, the numerals 4, 4 designate two lines of railway track over which tratfic is governed respectively by two railway signals S and -S. These signals may be of any type and may be cont-rolled in any suitable manner, these features forming no part of my invention. As is well known, the daylight indication of a railway signal is usually given-by the position of a semaphore arm, and the night indication by a light. 8 and 9 designate electric lamps for the night indication of signals S the evening andand S respectively. 22 designates a single phase transmission line which furnishes energy to the various parts of the signaling system such as the signal mechanisms, traclr circuits, etc. This line is connected with a source of current 23 through a transformer 24; 25 deslgnates a transformer located adacent the signals S and S, from which current is supplied to these signals and to the ad oining track circuits.

In my invention I provide an auxiliary circuit for the control of the signal lamps, one side of which circuit is formed by the transmission line 22 and the other side by a su table return conductor, herein shown as be1ng the ground. The transmission line is employed as one side of this auxiliary circuit by means of the following arrangement The middle point of the secondary of transformer 24' is connected with ground by means of a conductor 13, and the middle point of the primary of transformer 25 is slmilarly connected with ground by means of a conductor 14. Interposed inthe conductor 13 are asource of current M (here 'shOwn as being a separate generator) and a circuit controller 16. Interposed in the conductor 14 is a magnet 17 provided With an armature 18. The location of the transformer 24 and conductor 13 may be termed a point of control, since it is the point from which the signal lamps 8 and 9 are controlled. Lamps 8 and 9 are supplied with current from the transformer25, the circuit for these lamps being as follows-from the secondary of the transformer through wires 10 and 11, lamps 8 and 9, wire 28 to the transformer. Interposed between wires 10 and 11 is a circuit controller 12. 19' designates a ratchet wheel operated by armature 18 in the manner clearly shown in the draw-' ings. Operatively connected with the ratchet wheel is a cam wheel 20 which 0perates the circuit controller 12 through the medium of a link and roller 21. The construction is such that successive operation of the armature 18 will move the cam wheel 20 to such positions as to alternately open and close the circuit controller 12.

The operation of the system is as follows-VVhen it is desired to illuminate the lamps 8 and 9, the circuit controller 16 is momentarily closed, thereby causing magnet 17 to close circuit controller 12. When 1t is desired to extinguish the lamps, circuit controller 16 is again momentarily closed, causing magnet 17 to open circuit controller 12. It will be noted that current is consumed by 6 the magnet- 17 only at such time as an operation of circuit controller 12 is desired, and then only for a moment of time.

In the system shown in Fig. 2 the transmission line 1 is of the three-phase threewire type, and the conductors 13 and 14 are 2 the transformers at the generating station 01' control point are indicated'diagrammatically as connected in Y or in star, I have shown for illustrative purposes the transformers at the signal location connected in T, or in other words, with the well known three-phase two-phase connection. However the transformers are connected, the connection of the control circuit thereto should be made at the neutral point, which is always the geometric center of the triangle formed by the terminals of the transformer primary windings. The remaining parts of the system shown in'Fig. 2 are the same as those in Fig. 1, hence no further explanation is required.

Although I have herein shown a control system embodying my invention applied to be applied to a railway having any number v of tracks and any arrangement of signals.

Although I have herein shown and described only one form of lamp control system embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claim without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is In railway signaling, a transmission line, transformers distributed along the line for supplying the signaling apparatus With current, electric lamps for the signals, means for connecting and disconnecting each lamp to and from the secondary of an adjacent transformer, and a control circuit for said means including the conductors of the transmission line and a controlling device located at a distant point.

In testimony whereof I aflix my signature in presence of two witnesses.

LAURENCE A. HAWKINS. Witnesses:

BENJAMIN B. HULL, MARGARET E. WOOLLEY. 

